Device for forming far-reaching sound pencils and application of latter



- A 1,653,119 1927' A .1. B. PERRI'NET AL DEVICE FOR FORMING FAR REACHING SOUND PENCILS AND APPLICATION 01' LATTER Filed July 16, 1925 Dec. 20, 1927.

J. B. PERRIN ET AL.

DEVICE EOR FORMING FAR REACHING SOUND PENCILS AND APPLICATION OF LATTBR Filed July 16, 1925 3 Sheets-Shoot 2 Dec. 20, 1927.

J. B. PERRIN ET AL DEVICE FOR FORMING FAR REACHING SOUND PENCILS AND APPLICATION OF LATTER 3 Sheets-Sheet s The sound is transmitted through a tube,

Mes nezaio za i 1,653,119

UNITED" STATES- PATENT OFFICE.

max-names: mm, mm mus mm, am: 11mins nuennm mm JOSEPH 31mm, on runs, men.

nnvrcn ronromume FAB-REACHING somrnncms an) arrmcanorr or m'r'rnn. Application ma my 1a, was, Serial Io. 44,080, and m trance m :1, m4.

Present invention has for itspbject. a do v The sound pencil allows very frequent alv vice for guiding a sound 61111881011 and g1 vternations of sound and silence in chosen ing it a greate; reach byconcentratmg its po nt f d flect d i di all a f energy'in a given direction. Thlsprovidcs this point, the sound being nevertheless 5 for the formation of asort of a sound pen emitted continuously by the source at' a oil. The invention has also for its obiect stated frequency; this is very advantageous, several applications of this sound .penci es fifially when electric fog-horns are used.

length and diameter of which are adapted to used in the case of light houses comprising" 69 shape of which is c the pitch of the sound, from the source up isolated lights or a number of lights of di to an acoustic device which changes the net ferent colours, steady or revolving,,prov id ural s herical wave which would normally ing for simple 'or combined flashes, mn be bear the sound throu h theair into a wave used with the I, sound pencils. Thus low i iosen (at least. at the sounds of a given note can be used in lieu 35 start) and is preferably flat. of redlights and hi h ,sounds ofreen This can be done by bringing the sound lights, with any num r of interm' 'ar'y from the end of the tube which is the far well defined sounds between these.

thest from the source up to different points The theoryshows that a secondary penof a suitable surface, by paths of equal 011 can be produced in the-direction opposite length so that the sound enters the atmosto that of the principal pencil; this secondphere in phase. on the different points of this ary pencil is done. away with or weakened by surface which determines the shape of the giving the periphery of the emitting surface, sonorous wave at the start. a suitable'chosen or calculated shape which This'wave can be given a spherical (conmust not he a circle round the axis of the cave or convex) a cylindrical or a flat shape.- principal pencil and is preferably square.

In latter case, more particularly, the same i lhe advantages of the invention will. be arguments as those given in optics for exgiven hereunder with the description of the -pla'ining diffraction can be used whereby the appended drawings which show by way of formation of a sound (pencil can be foreseen example several forms of execution of the as and its size calculate invention and several applications thereof. In its applications, the sound-pencil can Fig.1 is a diagrammatical view of the v either move in 'a plane or in all-directions or whole device, the sound being 'ven' outby a be stationary. It can sweep all or part of a fog horn actuated by a small e ectric motor.

. plane or of space. Suitably disposed screens Fig. 2-is. a section through one ,of-thc can provide at will for silent zones. p acoustic paths of equal len hwhich lead the Two-or more moving or stationary sound sound from one end to t e tube connected ncils can start from the same source... with thesource to the surface'from" which heir axes can coincide or else be shifted by the sound is transmitted.

' a variable or stationaryangle. They can r0 Fig. 3'is a front view of one ofthe cirtatein'the same or in opposite directions. cular cells adapted for emitting a fiat wave. .Two pencils having the same origin and Fig. 4 shows a group of the pencils derotating with equal s eeds in opposite discribed as used on board a ship and oscillatrections coincide perio ically'along one same ing round a point.

direction characterized for the observer by Fig. 5 shows by way of example, how this the-synchronism of the two perceptions. oscillating movement can he obtained.- Two pencils can be distinguished one from Figs. 6 and 7 are diagrammatical figures the other by the pitch or pitches of the sound v relating to a form of execution wherein each transmitted, by its strength, by the angle pencil'sweeps a given angular sect0r' byromade with a given direction, or by the als tating with a uniform speed.- ternation of'the rotation of the pencils or of p the sound emissions. g the two pencils come from different sources.

short all the combinations known or modificationof 7 wherein wireless receiving post. p

Figs. 11 and 12 relate to the application to i a phonograph.

Fig. 13 relates to the application to an ordi I nary automobile horn. N

Fig. 1 1 relates to the application to an electromagnetic horn.

According to Fig. 1 the fog-horn 1 is actuated by a small electric motor fed by a sup ply 2 provided with a resistance 3 along which an index 4 can be moved so as to control the pitch of the sound emitted by the foghorn.

atter is connected; through a long tube 5 with the device omitting the flat wave. This device comprises in the example depicted on Figs. 1 and 2, four cells such as 7, each of which comprises a surface of revolution such as will oblige the diiierent fractional waves passing through the tube 9 to move by paths of equal length before arriving at the basis of the surface of revolution.

The interior of this surface is divided by a suitable number (six or eight for instance) of radial plane partitions such as (1-6, cd (Figs. 2 and 3). The four tubes such as 9 all start from a general collector 10 wherein ends the tube 5. The tubes 9 must have exactly the same length.

The tube 5 connecting the device emitting fiat waves to the fog-horn comprises a cer tain number of segments connected by the stationary threaded connections 11, 12, 13, 14, 15, 16. Moreover a rotating connection 17 provided if necessary with a ball bearing allows the part 5' of the tube 5 which is the nearest to the wave transmitter to rotate by 360, the rest of the tube 5 remaining stationary so as to allow the said transmitter to be directed in all azimuths.

The flat wave emitting device is borne by a support 18 top part of which bears a sleeve 19 wherein a' spindle 20 can rotate. This spindle is secured to the tube 5.

When the apparatus is used, the plane of emission can be set in a given direction wherein the sound will be diffused almost exclusively. Or else this plane of emission can be rotated so as to make the sound pencil sweep a plane.

By modifying the above described device through using either a supple tube or a tube provided with two rectangular axial articulations, the pencil can be easily set in any direction of space.

In order that the size of the apparatus should suit the desired pitch of sound and the opening or field of the pencil, the source of the sound can be chosen and also the length and. diameter of the tube 5. Lat ter may comprise a sliding part for finishing the adjustment, the number, size and opening diameter of the acoustic cells, the synchronous transmitting surface, its curvature, the shape of its periphery can also be modified for controlling the pitch of the sound and the field of the sound pencil.

The sound projector which is the object of the invention can project one or more pencils oscillating round a point so as to sweep a space inside a given angle and to leave a region in silence. A form of execution of such a projector is given by way of example on appended Figure 4.

On starboard of the ship 21 is disposed at 22 a device adapted to send forth three pencils F F, F which can sweep an angle of 180 for instance between the directions T T on larboard at 23 another device is disposed which transmits two pencils F F oscillating between the directions 13 B This provides for the following advantages with reference to the pencils movable in all directions described hereinbefore.

1. It allows a longer sound emission for an equal number of passages of the sound pencil or pencils in a given direction, the time of emission being for instance double when the sweeping angle is 180 as on the example shown.

2. When used on a ship if the pitch of the sound in the several pencils F F F of the same group is different whereby the sound of each pencil can be easily recognized, the time between the passage of each of these three pencils in front of an observer-gives latter the head of the ship. Thus if the times between two passages are equal it shows the observer is on the bisector of the sweeping angle, that is abreast the ship. If the two groups F F F 3 and F F F are heard in quick succession it means the observer is nearer fore than aft. Reversely of the groups F F F and F F F are heard in quick succession, it means the observer is nearer aft than fore.

Thus the problem of the position and of the direction of the ship is quite solved.

The acoustic device can be caused to oscillate by any suitable means. A form of execution of such means is shown diagrammati cally by way of example on appended Figure 5.

In a suitably excentered point 24 of a circular plate 25, rotating round its center 26, a rod 27 is pivoted, the other extremity of said rod being pivoted in a suitably excentered point 28 of the device 29 for transmitting the guided waves.

Fig. 7 shows an example of the use of the combination of two pencils moving constantly in opposite directions.

A first sound pencil starting from O and frequency of which is N moves with a uniform speed along the sector A O B; a second sound pencil also starting from 0 but havllll ing a frequency N moves with a uniform speed in a direction opposite to that of the first pencll along the sector A O B.

The two pencils start respectively from O A and O A and arrive respectively at O B and O B at the same time. The two sectors swept by the pencils overlap and have in common the sector B O B, the twopencils crossing each other along 0 X, bisector of the angle B O B. The several regions of the plane are thus characterized as follows:

Sector A O A: Silence.

Sector A O B: Only the pencil N is heard.

Sector B O X: The two pencils are heard in quick succession in the order N N Along O X: The two sounds are heard siinultaneously.

Sector-X O B: The two pencils are heard in quick succession in the order N N Sector B O A: The pencil N is heard alone.

Of course the angular values of these several sectors can be modifiedat will according to the aim one has in view.

In case the device is used on board a ship, the direction 0 X will coincide with the fore direction of the axis of the ship, the aft direction coinciding with the bisector of the silent sector A O A.

If the apparatus is used on the coast, the silent sector will take up a continental area and the direction 0 X will show the ships a direction which they are to either follow or avoid according to the conventions made.

If desired, the two sounds N N can be made more easily distinguishable by giving one of them an interrupted characteristic for instance through using a hollow core provided with suitable openings and rotating at a suitable speed.

The diagrammatical Fig. 8 relates to a modification wherein the two pencils have a different source, the pencil N being produced by O, and N by 0,. The coincidence of the two sounds appears to the observer when latter is on theline X X which is perpendicular to the line 0 O in its middle.

The source of the sound emitted used as explained hereinabove can be of any suitable kind; for instance it can comprise an electric fog-horn as stated above. Fig. 9 shows a form of execution of an electric turbine fog-horn sending the sound produced into a tube.

This fog-horn comprises a shut casing 30 wherein are located a motor 31 and a turbine (not shown). When the fog-horn.is started, the air is sucked through 32 at the end of the casing 30 and is driven on through the openings 33 disposed on the periphery of the casing 30. v,

Latter is disposed inside a chamber 34: surface of whichis of revolution; its cylindrical walls 35 are connected on one hand with the suction side of the casing 30 by means of a frusto-conical part 36 disposed laterally with reference to the openings 33 and on the other hand through a suitably sloping part 37 to a pipe 38 disposed in front of the axis of the casin 30. The sound emitted by the fog-horn is thus reflected by the frusto-conical part 36 and sent into the pipe 38, In order to avoid the eddies which might alter the sound, the casing 30 shows a conical projection 39 on its front wall, the sides whereof are parallel to the wall 37 of the chamber 34.

The fog-horn could be replaced by any other suitable source of sound, for instance, by a fog-horn actuated by compressed air or by steam, by a bell, by an apparatus such as a bugle or by any apparatus transforming into audible vibrations electric or electromagnetic vibrations such as a telephone vibrating plate whereof is adapted to transmit signals received by radio, etc.

The device as described hereinabove can be used for a great number of purposes of which only a few are given hereinafter by way of example.

1. Sound projector for emitting signals chiefly in foggy weather. The projector can be stationary or else revolve according as to whether the device transmitting the guided sounds is stationary or adapted to revolve. A

2. Acoustic telegraphy using Morse signals for instance, the sound projector being directed towards a given receiving station;

the necessary modulations can be obtained by opening or closing for instance the entrance of air into the fog-horn.

3. Signalling and alarm device between two distant points of a railway line, of a large plant, of a farm, etc. with the expenditure. of very little power.

4. Checking of the direction and of the head of a ship provided for instancewith two sound projectors on starboard and larboard or on fore and aft.

5. Fallingin of several ships sailing together.

6. Grouping of a number of sound projectors protected by .iron frames electrically controlled from a central control station in foggy weather for allowing the sea-farers to check the angular directions of these projectors and thereby to find their way into a The Figs. 11 and 12 relate to the application of the device to a phonograph. On

the central tube 41 of the-surface of revolution 40 is fitted a suitably curved tube 44 Fig. 13 relates to the application to an ordinary automobile horn. The tube 49 provided with a reed-pipe 50 and with a rubber bottle 51 expands at 52 into a surface of revolution. The edge of the bell thus formed can either be wide open as shown in full lines at 52 or else narrowed in as showed in dotted lines at 52". The free central part of the horn can be closed by a plate 53. It can also be used for re.- ceivin a light projector Comprising a lamp 54 an a reflector 55.

Lastly Fig. 14 shows the invention as used with an electromagnetic horn, the rear part 56 of the device receives the motor, the electromagnetic mechanism or other device which causes the plate 57 to vibrate.

The acoustic waves produced by latter are received In a surface of revolution 58 similar to that shown on Fig. 13 and also adapted to receive in its center a li ht projector constituted by the lamp 59 an the reflector 60. The rear art of' the alarm device turned towards t e driver can receive a mirposed in one plane, and tubes of equal length connecting the collector with the different cells.

Leeann horn actuated by said motor, a casing bounded by a surface of revolution enclosing the fog-horn and through which the sound produced by the fog-horn is adapted to ass, a stationary tube connected with sai casing, a rotatable tube connected therewith, a collector borne by said rotatable 2. A device for producing sound pencils comprising an electric motor, a turbine fogtube and connected therewith, a series of sound-emitting cells adapted to rotate with the rotatable tube and bounded by two substantially cup shaped surfaces of revolution, the several cells opening into the atmosphere along'annular surfaces all disposed in one plane, and tubes of equal length connecting the collector with the different cells.

3. A device for producing sound pencils comprising a source of acoustic waves, a stationary tube leading from said source, a rotatable tube connected therewith, a collector borne by said rotatable tube and connected therewith, a series of soundemitting cells adapted to rotate with the rotatable tube and bounded by two substantially cup shaped surfaces of revolution, the several cells opening into the atmosphere along annular surfaces all disposed in one plane, tubes of equal length connecting the collector with the different cells and means for making the rotatable part ofthe device move to and fro in a continuous manner between two given angular directions.

4. An arrangement comprising two devices as claimed in claim 2 and means for making the rotatable parts of the two devices move to and fro with a. uniform speed between two given an lar directions, the sectors swept between t ese couples of given directions beingfoverlapping and respectively travelled over at any moment in opposite directions. In testimony whereof we aflix our signatures.

JEAN-BAPTISTE PERRIN. ANDRE JULES mncaun.

namu LUGLIEN mu. Jostrn IENARD. I 

